//web或webapi获取表单数据流(批量文件上传)
        public jsonresult uploadfile()
        {
            //httppostedfilebase filebase = request.files[“filetouploadkeyid”];
            httppostedfilebase filebase = request.files[0]; //获取客户端上载的文件的集合

            string resulturl = string.empty;//相对文件路径
            string errmsg = string.empty;

            if (filebase == null || filebase.contentlength == 0)
            {
                errmsg = “文件为空”;
            }
            else
            {
                int maxsize = 1024 * 1024 * 4;
                if (filebase.inputstream.length > maxsize)
                {
                    errmsg = “文件过大”;
                }
                else
                {
                    try
                    {
                        //循环遍历批量上传的文件
                        for (int i = 0; i < request.files.count; i++)
                        {
                            filebase = request.files[i];
                            var name = system.io.path.getfilename(filebase.filename);
                            var filename = “/upload/” + datetime.now.tostring(“yymmddhhmmssffff”) + “.” + name.split(‘.’)[1];
                            var filepath = system.web.httpcontext.current.server.mappath(filename);
                            filebase.saveas(filepath);//保存文件

                            resulturl += filename + “;”;//拼接文件相对路径
                        }
                    }
                    catch
                    {
                        errmsg = “上传失败”;
                    }

                }
            }
            return json(new { errmsg = errmsg, resulturl = resulturl.trim(‘;’) });
        }